Torpedo arming device



June 20, 1961 w. B. ELMERQ TORPEDO ARMING DEVICE Filed Oct. 31, 1945 r ea J a s 8 W A w 3 A ,/\..e r a 7 w Q/OXM a q V a a An Mec/za/r/lsms[Irp/ode/ f waif/00170 fZafu/e INVENTOR V/M4075 [/mer BY ME, W

ATTORNEY w w-m My invention relates to an arming mechanism for a torpedoused as a mine.

Torpedo mines are provided with a mooring anchor and a cable attachingthe anchor to the torpedo and so paid out that thetorpedo is moored ataselected depth.

While the mooring anchor is in the torpedo the torpedo has a negativebouyancy and would normally sink, but when the torpedo is launched fromthe tube of a submarine or some other launching craft the anchor isreleased .from the anchor cavity in the torpedo as soon as the torpedois a short distance from the launching .craft.

.Safety features are provided 'to preclude the arming of the torpedowhile in the firing tube, or some other place on or near the launchingcraft. Some trigger mechanisms for arming are operated when the torpedois launched but safety to the launching craft and personnel make it verydesirable that the torpedo does not become armed except the torpedo beat a given distance from the launching craft and be at a depth greaterthan a given minimum.

One object of my invention is to effect arming of a torpedo mine whenthe torpedo is a selected distance from the launching craft.

Another object of my invention is to effect arming of a torpedo mineonly when the torpedo is at a depth greater than ;a given A stillfurther object of my invention is to elfect the arming of a torpedo minewhen the torpedo has travelled a given distance in the water from thefiring position and at a depth greater than a selected depth.

A broad object of my invention is to prevent detonation of the explosivecharge in a torpedo mine while yet near the launching craft.

Other objects and advantages will become more apparent from a study offollowing specification and the accompanying drawing, in which:

FIGURE 1 shows the afterbody of a torpedo mine broken open to illustratea side view of the mechanical details of my invention; and

FIG. 2 shows the essential electrical circuits for effecting the novelresults of my invention.

When the torpedo is launched, or fired from the firing tube of asubmarine, the inertia trip mechanism 1, having the pivoted weight 2 andovercenter spring arrangement 3, closes the contacts 4 to thus providelive circuits to the exploder mechanisms, the control and propulsioncircuits.

My invention is primarily concerned with the switch S and the mechanismsfor closing the contacts of this switch only after the torpedo mine is asafe distance from the submarine and at a depth greater than a selectedminimum.

When the torpedo is launched, the flow of the water over the propellercauses rotation of the propeller and shaft. This rotation of thepropeller is found to take place at water speeds relative to the torpedoin excess of five knots per hour. Since the torpedo is launched at muchgreater speed than five knots per hour and does not drop to a lesserspeed until the torpedo is some considerable distance from the firingtube, I take advantage of this propeller rotation to actuate switch S.

In my construction I provide the propulsion shaft 5 with a worm 6. On asuitable frame structure 7, bolted nited States Patent 0 2,988,992Patented June 20, 1961 2 to the torpedo afterbody 8 at 9 and 10 onsuitable brackets provided for thepurpose, .I rotatably mount the Wormwheel 11 in such a manner that the worm wheel 11 is permanently in meshwith the Worm .6. The shaft 12 for the worm wheel also carries a pinion13.

To the forward end of the frame I secure a bellows closed at both theforward and aft end, except that I connect the interior of the bellowsto the pressure of the seawater by means of the nipples 15 and 1 6 andpipe coupling 17. The aft end of the bellows will thus move as afunction of the pressure of the water outside of the torpedo shell8.

To the aft end of the bellows I secure the upper or movable end of therocker arm 18 which is pivoted at 1-9 on the frame 7.

On the movable or upper end of the rocker arm .18 I mount apin 20 onwhich the gearsector 21 is pivotally mounted. 'The gear sector isnormally biased for counterclockwise rotation on its pivot by the spring22, which is at its forward end secured to the frame '7 and at its aftend secured to the sector 21 at a point above the pivot pin 20. Thespring arrangement thus provides an overcenter function for the gearsector. The sector is limited in its angular motion by stops discussedheregreater than a twenty foot head of water. A decrease of pressurebelow a twenty foot head causes the bellows to withdraw the sector 21from the in-mesh relation with the pinion 13. This is the relation shownin FIG. 1.

After firing of the torpedo if the depth is more than twenty feet thesector '21 and pinion 13 are thrown into mesh and since the shaft 5 isrotating in the direction indicated the, sector is rotated in aclockwise direction.

The dead center of the overcenter arrangement is located on the sectorgear near the end of the gear travel. If the gears 21 and-13 disengageat any point before reaching the center, the sector 21 is thrown back.to the position shown. If, however, the pressure is maintained until thesector 21 moves oif the pinion 13, the overcenter spring 22 then swingsthe gear sector clockwise through an additional small angle to clear thepinion 13.

The stop for the sector 21 in the clockwise direction consists of asmall micro switch S of the over center type. The switch S is actuatedby the tab 23 on the sector 21. The arming function required of mydevice is thus completed.

The stop for the gear sector 21 in the counterclockwise direction isformed by a leaf spring 24 having an aft end extending below the shaft12 for the pinion 13 and worm wheel 11. Should the propeller, for somereason, he turned a short distance in the reverse, or wrong direction,during launching, or any other time, the sector 21 is moved 011 thepinion 13 against the leaf spring 24. Upon-normal rotation of thepropeller, the leaf spring 24 returns the sector 21 to such a positionthat the sector 21 and pinion 13 are in operative relation.

The gear ratios of the gears shown are so selected that the torpedo minetravels the required distance through the water before arming occurs.

Should the propeller be turned by hand or otherwise while out of thewater, arming cannot occur since the hydrostatic pressure is absent fromthe bellows 14. Further, should the torpedo-mine stick in the tubeduring launching after emerging far enough for the anchor to drop fromits cavity, arming is avoided because the propeller will fail to turn inthe forward direction.

propeller while being rotated by the water flowing over the propellerblades during launching, arming means for the torpedo, pressure actuatedmeans responsive to the hydrostatic head to which the torpedo issubjected, and means responsive to the joint action of said distancemeans and pressure actuated means for effecting operation of said armingmeans for the torpedo.

2. In a torpedo to be operated in the nature of a mine, ,in combination,an ignitor for the main charge of explosive, arming means for theignitor, exploder means for energizing said ignitor, means responsiveboth to the,hydrostatic head above the torpedo and the distance oftravel of the torpedo from its launching position for effecting theoperation of said arming means for said ignitor after the torpedo is ata depth greater than a given minimum and at a distance greater than agiven minimum from the launching position of the torpedomine.

3. In a torpedo to be operated as a mine provided with a propeller forself-propulsion and of the type that is launched from a launching craftfrom a thing tube, or otherwise, in combination, transmission gearingoperated from the propeller shaft by rotation of the propeller by thewater flowing over the propeller blades after launching, a bellowssubject to the pressure of the Water surrounding the torpedo, a gearsector operated into meshing relation with said transmission gearing bysaid bellows when the hydrostatic head is greater than a given minimum,and means for effecting an arming action after a predetermined angularrotation of the gear sector.

4. Ina torpedo to be operated as a mine and provided with a propellerfor self-propulsion and of the type that is launched from a launchingcraft from a firing tube, or otherwise, in combination, transmissiongearing operated from the propeller shaft by rotation of the propellerby the water flowing over the propeller blades after launching, abellows subject to the pressure of the water surrounding the torpedo, agear sector operated into meshing relation with said transmissiongearing by said bellows when the hydrostatic head is greater than agiven minimum, means for eiiecting an arming action after v 4 apredetermined angular rotation of the gear sector, and means fordisengaging the gear sector and the transmission gearing upon rotationof the propellers in the wrong direction.

5. In ordnance equipment of the self-propelled type but which islaunched from a launching craft and which contains a charge ofexplosive, in combination, travel responsive means for measuring thedistance of travel of the equipment from the launching position, anignitor for the charge of explosive in the equipment, exploder meansoperated in response to the proximity of a target to the equipment forenergizing the ignitor, arming means for the ignitor, pressureresponsive means, and means responsive both to the pressure of themedium surrounding the equipment as determined by the pressureresponsive means and the distance of the equipment from the launchingcraft as determined by the travel responsive means for eflecting theoperation of the arming means when. the equipment is at a greaterdistance from the launching craft than a given minimum and the pressureon the equipment is greater than a given minimum.

6. In a torpedo to be operated in the nature of a mine provided with apropeller and drive shaft therefor, which is setin operation forself-propulsion upon reception of target signals at the moored positionof the torpedo but whichtorpedo is of the type to be launched atrelatively high speed from a launching craft, in combination, a wormmounted on the drive shaft which worm is driven by the rotation of thepropeller by the water flowing over the propeller blades duringlaunching, gears operated by the worm, a gear sector disposed to beplaced in mesh with said gears, hydrostatic means for moving the gearsector in mesh with said gears at a hydrostatic head greater than agiven minimum, and switching means operated by a predetermined angularmovement of the sector. l 1:

References Cited in the file of this patent UNITED STATES PATENTS644,321 Gathmann Feb. 27, 1900 1,382,374 Maxim June 21, 1921 1,626,794Dieter May 3, 1927 2,060,206 Hammond Nov. 10, 1936 FOREIGN PATENTS212,774 Germany Aug. 7, 1909 156,814 Great Britain I an. 20, 1921

